Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. There are three main types of learning: classical conditioning, operant conditioning, and observational learning. Both classical and operant conditioning are forms of associative learning, in which associations are made between events that occur together.

Learned helplessness, in psychology, a mental state in which an organism forced to bear aversive stimuli, or stimuli that are painful or otherwise unpleasant, becomes unable or unwilling to avoid subsequent encounters with those stimuli, even if they are “escapable,” presumably because it has learned that it cannot control the situation.

Learned helplessness occurs when an individual continuously faces a negative, uncontrollable situation and stops trying to change their circumstances, even when they have the ability to do so. For example, a smoker may repeatedly try and fail to quit. Three components are necessary for learned helplessness to be present: contingency, cognition, and behavior. Learned helplessness theory is the view that clinical depression and related mental illnesses may result from such real or perceived absence of control over the outcome of a situation.

Schedules of reinforcement are the precise rules that are used to present (or to remove) reinforcers (or punishers) following a specified operant behavior. These rules are defined in terms of the time and/or the number of responses required in order to present (or to remove) a reinforcer (or a punisher).

There are four basic types of intermittent schedules of reinforcement and these are:

• Fixed-Ratio (FR) Schedule.
• Fixed Interval (FI) Schedule.
• Variable-Ratio (VR) schedule.
• Variable-Interval (VI) schedule.

Observational learning describes the process of learning through watching others, retaining the information, and then later replicating the behaviors that were observed. ... A tremendous amount of learning happens through this process of watching and imitating others. In psychology, this is known as observational learning. Observational learning occurs through observing negative and positive behaviors. Bandura believes in reciprocal determinism in which the environment can influence people's behavior and vice versa. For instance, the Bobo doll experiment shows that the model, in a determined environment, affects children's behavior.

Operant conditioning (also called instrumental conditioning) is a type of associative learning process through which the strength of a behavior is modified by reinforcement or punishment. It is also a procedure that is used to bring about such learning. ... Operant behavior is said to be "voluntary". Skinner in his theory of operant conditioning. ... The reward is a reinforcing stimulus. Skinner showed how positive reinforcement worked by placing a hungry rat in his Skinner box. The box contained a lever on the side, and as the rat moved about the box, it would accidentally knock the lever.

There are three main types of learning: classical conditioning, operant conditioning, and observational learning. Both classical and operant conditioning are forms of associative learning, in which associations are made between events that occur together.

Some common memory disorders include dementia, Alzheimer's disease, and encephalopathy. Dementia is associated with general cognitive decline and failure of the memory process.

11-15 years: The adolescents in this age develop formal operational thought, which leads to a hypothetical thinking and are able to apply logic abstractly. They also develop a special kind of egocentrism of imaginary audience and personal fable.

Adolescence begins at puberty, and is the transition from childhood to adulthood. Physical changes in adolescence include the development of secondary *** characteristics, hormonal changes, and spurt in growth. The major developmental tasks for the adolescent include identity formation and coming to terms with biological changes taking place.

1. The autonomic nervous system is divided into two main divisions: Sympathetic nervous system 
2. Parasympathetic nervous system

These both are antagonistic in working i.e. they work opposite to each other. This is because of the different neurotransmitters secreted by the axon terminals of the nervous systems. The neurotransmitter of the parasympathetic nervous system is acetylcholine whereas in the case of the sympathetic nervous system is adrenaline/epinephrine. Sympathetic works in the case of an emergency while parasympathetic works under normal conditions.

Examples are:

1. Heart: SNS speeds up the heartbeat whereas the PSNS slows down the heartbeat.

2. Eyes: SNS dilates the pupils whereas the PSNS constricts the pupil or bring it in the normal condition.

3. Lungs: SNS dilates the bronchioles for greater alveolar oxygen exchange while PSNS constricts the bronchioles when oxygen requirement diminishes.

Speed test: In a speed test, there is a time limit within which the test taker is required to answer all the items. Such a test evaluates the individual on the basis of time taken to answer the items accurately. In a speed test, all the items are of the same degree of difficulty.

Power test: Power test assesses the underlying ability of the individuals by allowing them sufficient time. These tests do not have any time limit. The items are generally arranged in an increasing order of difficulty.

Speed test: In a speed test, there is a time limit within which the test taker is required to answer all the items. Such a test evaluates the individual on the basis of time taken to answer the items accurately. In a speed test, all the items are of the same degree of difficulty.
Power test: Power test assesses the underlying ability of the individuals by allowing them sufficient time. These tests do not have any time limit. The items are generally arranged in an increasing order of difficulty.

The monocular cues of depth perception induce depth in objects when viewed through a single eye. They are also known as pictorial cues as they are used by artists to induce depth in two-dimensional paintings. Important monocular cues are relative size and height, interposition, linear and aerial perspective, light and shade, texture gradient, and motion parallax.

The binocular cues of depth perception are provided by both the eyes in three-dimensional spaces. Their role in the perception of depth is as follows:

(i) Retinal or Binocular disparity: It occurs when the two eyes have different locations in the head and are separated horizontally with a difference of 6.5 centimetres. The difference in the images formed by the eyes is due to the retinal disparity. Large retinal disparity means a close object and small retinal disparity means a distant object.

(ii) Convergence: When the eyes converge inward to bring the image on the fovea of each eye, a group of muscles sends messages to the brain which are interpreted as cues to the perception of depth. The degree of convergence decreases with an increase in distance of the object.

(iii) Accommodation: It is the process through which the image is focussed on the retina with the help of a ciliary muscle. These muscles change the thickness of the eye lens. The degree of contraction of the muscles provides a cue to distance. The muscles relax when the object is distant and contract when the object is near.

There are two general processes involved in sensation and perception. Bottom-up processing refers to processing sensory information as it is coming in. In other words, if I flash a random picture on the screen, your eyes detect the features, your brain pieces it together, and you perceive a picture of an eagle. What you see is based only on the sensory information coming in. Bottom-up refers to the way it is built up from the smallest pieces of sensory information.



Top-down processing, on the other hand, refers to perception that is driven by cognition. Your brain applies what it knows and what it expects to perceive and fills in the blanks, so to speak. First, let us look at a visual example:

Look at the shape in the box to the right. Seen alone, your brain engages in bottom-up processing. There are two thick vertical lines and three thin horizontal lines. There is no context to give it a specific meaning, so there is no top-down processing involved.


Now, look at the same shape in two different contexts.

Surrounded by sequential letters, your brain expects the shape to be a letter and to complete the sequence. In that context, you perceive the lines to form the shape of the letter “B.” Surrounded by numbers, the same shape now looks like the number “13.” When given a context, your perception is driven by your cognitive expectations. Now you are processing the shape in a top-down fashion.

Next, watch this video for an example of top-down processing with auditory stimuli. Note that at the end, once you have heard the full sentence, you can understand it even when it is broken up again. A “phoneme” is just a basic unit of speech sound.
 

The Principle of Proximity
Objects that are close together in space or time
are perceived as belonging together or as a
group. For example, Fig.5.7 does not look like
a square pattern of dots, but as a series of
columns of dots. Similarly, Fig.5.7 also looks
like a group of dots together in rows

Click on the given link and go to page no. 17

<a href="https://ncert.nic.in/ncerts/l/kepy105.pdf" ping="/url?sa=t&source=web&rct=j&url=https://ncert.nic.in/ncerts/l/kepy105.pdf&ved=2ahUKEwi6z7-lmKztAhVdxTgGHe8fBLYQFjAMegQIGxAC" rel="noopener" target="_blank">Chapter 5 - Sensory, Attentional and Perceptual ... - ncert</a>

Monocular cues of depth perception are effective when the objects are viewed with only one eye. These cues are often used by artists to induce depth in two dimensional paintings. Hence, they are also known as pictorial cues.

Role of binocular cues in the perception of depth: Some important cues to depth perception in three dimenstional space provided by binocular cues (both eyes). Some of them are as follows:

(i) Retinal or Binocular Disparity: Retinal disparity occurs because the two eyes have different locations in the head. They are separated from each other horizontally by a distance of about 6.5 centimeters. Because of this distance, the image formed on the retina of each eye of the same object is slightly different. This difference between the two images is called retinal disparity. The brain interprets a large retinal disparity to mean a close object and a small retinal disparity to mean a distant object, as a disparity is less for distant objects and more for the near objects.

(ii) Convergence: When we see a nearby object our eyes converge inward in order to bring the image on the fovea of each eye. A group of muscles send messages to the brain regarding the degree to which eyes are turning inward, and these messages are interpreted as cues to the perception of depth. The degree of convergence decreases as the object moves further away from the observer. One can experience convergence by holding a finger in front of his nose and slowly bringing it closer. The more his eyes turn inward or converge, the nearer the object appears in space.

(iii) Accommodation: Accommodation refers to a process by which we focus the image on the retina with the help of ciliary muscles. These muscles change the thickness of the lens of the eye. If the object gets away (more than 2 meters), the muscle is relaxed. As the object moves nearer, the muscle contracts and the thickness of the lens increases. The signal about the degree of contraction of the muscle is sent to the brain, which provides the cue for distance.

Socio-cultural factors influence our perceptions by generating differential familiarity and salience of stimuli as well as certain habits of perception. People living in different cultural settings have varying perceptions like identification of objects and interpretation of depth. For example, in the study carried out by psychologists in Africa and Europe, it was observed that the Africans have a greater susceptibility to horizontal-vertical illusions as they live in dense forests and regularly experience verticality which overestimated.

Europeans on the other hand, have a greater susceptibility to Muller-Lyer illusion as they live in an environment that has right angles. Hence, they underestimate the length of lines characterised by the enclosure.

Socio-cultural factors influence our perceptions by generating differential familiarity and salience of stimuli as well as certain habits of perception. People living in different cultural settings have varying perceptions like identification of objects and interpretation of depth.

ADHD stands for attention deficit hyperactivity disorder, a complex brain disorder that impacts approximately 11% of children and almost 5% of adults in the U.S

Common ADHD symptoms include:

• inattention
• lack of focus
• poor time management
• weak impulse control
• exaggerated emotions
• hyperfocus
• hyperactivity
• executive dysfunction

Selective attention is concerned mainly with the selection of a limited number of stimuli from a large number of stimuli whereas sustained attention refers to focusing of awareness on specific objects while excluding others for the movement

Filter Theory was developed by Broadbent (1956). According to this theory, many stimuli simultaneously enter our receptors creating a kind of‘bottleneck’ situation. Moving through the short-term memory system, they enter the selective filter, which allows only one stimulus to pass through for higher levels of processing. Other stimuli are screened out at that moment of time. Thus, we become aware of only that stimulus, which gets access through the selective filter.

Perceptions of human beings are not always veridical. Sometimes he fails to interprete the sensory information correctly. This results in a mismatch between the physical stimuli and its perception. These misperceptions resulting from misinterpretation of information received by our sensory organs are generally termed as illusions. Illusion result from an external stimulus situation and generate the same kind of experience in each individual. Although illusions can be experienced by the stimulation of any of our senses, psychologists have studied them more commonly in the visual than in other senses modalities.

Illusions occur because of a result of a mismatch between the physical stimuli and its perception by the individual. The mismatch is caused by incorrect interpretation of information received by sensory organs. Illusions are called primitive organisations as they are generated by an external stimulus situation that generates the same kind of experience in all the individuals. Some illusions are universal in nature as they are found in all individuals. They are also known as universal illusions or permanent illusions because they do not change with experience and practice. Contrary to this, illusions that vary in different individuals are known as personal illusions.

Space is perceived in three dimensions. This is because of our ability to transfer a two-dimensional retinal vision into a three dimensional perception. Spatial attributes of objects like, size, shape and distance between objects also contribute towards the perception of space.

The visual field or surface in which things exist, move or can be placed is called space. We perceive not only the spatial attributes (e.g., size, shape, direction) of various objects, but also the distance between the objects found in this space. While the images of objects projected on to our retina are flat and two dimensional (left, right, up, down) we still perceive three dimensions in the space. It occurs due to our ability to transfer a two dimensional retinal vision into a three dimensional perception.

The process through which certain stimuli are selected from a group of others is generally referred to as attention.
The properties of attention are selection, alertness, concentration and search.

1. Selection— A large number of stimuli impinge upon our sense organs simultaneously, but we do not notice all of them at the same time. Only a selected few of them are noticed, e.g. when you enter your classroom you encounter several things like doors, walls, windows etc but you selectively focus only on one or two of them at one time.
2. Alertness— Alertness refers to an individual’s readiness to deal with stimuli that appear before him/her. e.g. while participating in a race in your school you must have seen the participants on the starting line in an alert state waiting for the whistle to blow in order to run.
3. Concentration— Concentration refers to focusing of awareness on certain specific objects while excluding others for the moment, e.g. in the classroom a student concentrates on the teacher’s lecture and ignores all sorts of noises coming from different comers of the school.
4.  Search— In search an observer looks for some specified subset of objects among a set of objects, e.g. when we go to school to fetch our younger sister and brother from the school we just look for them among innumerable boys and girls.

The process through which certain stimuli are selected from a group of others is generally referred to as attention.

Attention has different properties such as selection, alertness, concentration, and search.

(i) Selection: A large number of stimuli impinge upon our sense organs simultaneously but we do not notice all of them at the same time. Only a selected few of them are noticed. For example, when a student enters his classroom he encounters several things in it, such as doors, walls, windows, paintings on walls, tables, chairs, students, school bags, etc., but he selectively focus only on one or two of them at one time.

(ii) Alertness: It refers to an individual’s readiness to deal with stimuli that appear before him/her. For example while participating in a race in school, a student can see the participants on the starting line in an alert state waiting for the whistle to blow in order to run.

(iii) Concentration: It refers to focusing of awareness on certain specific objects while excluding others for the moment. For example in the classroom, a student concentrates on the teacher’s lecture and ignores all sorts of noise coming from different corners of the school.

(iv) Search: In search an observer looks for some specified subject or object among a set of objects. Example : When you go to fetch your younger sister and brother from the school, you just look for them among many boys and girls. All these activities require some kind of effort on the part of the people.

The functional limitations of sense organs of human beings refer to their limited range of stimulation. In order to be noticed, a stimulus has to be of an optimal intensity and magnitude. Thus, the stimulus has to carry a minimum value or weight. For example, our ears cannot hear very faint or loud sounds. Similarly, our eyes cannot see objects in very dim or very bright light.

Our sense organs provide us with first hand information about our external or internal world. Different sense organs deal with different forms of stimuli and serve different purposes. Each sense organ is highly specialised for dealing with a particular kind of information. However, all sense organs function with certain limitations. For example, our eyes cannot see things which are very dim or very bright. Similarly, our ears cannot hear very faint or very loud sounds. As human beings, we function within a limited range of stimulation. A stimulus, to be noticed by a sensory receptor, has to be of an optimal intensity or magnitude. In order to be noticed, a stimulus has to carry a minimum value or weight.

The minimum value of a stimulus required to activate a given sensory system is called absolute limen (AL). Absolute limen is not a fixed point, instead it varies considerably across individuals and situations depending on the people’s organic conditions and their motivational states. Hence, it is assessed on the basis of a number of trials. Further, it is not possible to differentiate between all stimuli. In order to notice two stimuli are different from each other. These has to be some minimum difference between the value of those stimuli. The smallest difference in the value of two stimuli that is necessary to notice them as different is termed as difference limen (DL). Thus, it is not possible to understand sensations without the AL and DL of different types of stimuli.

Besides the stimulus characteristics, sensory processes also depend on other characteristics. Sense organs and the neural pathways connecting them to various brain centres also play a vital role in this process. A sense organ receives the stimulus and encodes it as an electrical impulse. For being noticed this electrical impulse must reach the higher brain centres. Any structural or functional defect or damage in the receptor organs, its neural pathway, or the concerned brain area may lead to a partial or complete loss of sensation.