Captain Psychology

Perception

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Speech Perception

Speech Perception

  • 3 components of Speech Perception

    • 1. Physical signal

      • Process sound waves

      • Varies in 3 parameters

        • Amplitude

        • Frequency

        • Time

    • 2. Extract  phonemes

      • The smallest unit in a language that is capable of conveying a distinction in meaning

      • Make fine distinctions between similar patterns of sound

      • Examples

        • Buh or Tuh

        • M of mat and B of bat

      • Phone = a particular sound used by any language

      • eg the sound [r]

      • Phoneme = a sound used in contrast to another in a particular language

        • eg  the category  /r/ as distinct from /l/ 

        • 1. Phoneme extraction is categorical

          • i.e. if physical characteristics of the signal are changed slowly, there is a sudden change in which phoneme is perceived

        • 2. The speech recognition system can modify fuzzy input to give the listener the correct sound

    • 3. Perception

      • Extract meaning

      • Allows us to recognize the same sounds spoken in different ways

        • e.g. by two different people

      • There are no natural breaks in speech

      • We “hallucinate” word boundaries

        • Oronyms

          • Two or more sentences that use the same sounds but have different words

          • Such as

            • Scuse me while I kiss the sky

            • Scuse me while I kiss this guy

          • Or

            • Some others I know

            • Some mothers I know

        • Speech perception errors

          • Eugene O’neil won a Pullet Surprise

Research methods

  • Voice-Onset Time

    • The amount of time between the release of a stop consonant and the onset of glottal vibrations in the following vowel

    • In English, if we start the laryngeal tone exactly at the beginning of the “P” sound, it becomes (is perceived as) the “B” sound

    • If we delay progressively longer in small increments the beginning of the voice (voice onset time), there is a point in time that it would become the “P” sound

    • VOT may be negative, zero or positive

      • Zero

        • Vocal-cord vibration has begun simultaneously with the release of the plosive consonant

        • A voiceless unaspirated stop (eg. [k]) has zero VOT

      • Negative

        • Vibration beginning earlier than the release

        • A pre-voiced stop (eg. [ɡ]) has negative VOT

      • Positive

        • Vibration beginning after the release

        • A voiceless aspirated stop (eg. [k ʰ]) has positive VOT

    • Different languages have different methods of phonetic realization of this feature

Categorical Perception

  • Definition

    • Sharp phoneme boundary

    • Discrimination peak at phoneme boundary

    • Discrimination predicted from identification

      • only “different” if different phoneme

  • Occurs with consonants, not vowels

  • Not restricted to speech

    • Also found in comparison of musical intervals

  • Not restricted to humans

    • Chinchillas and quails show the same Voice Onset Time boundary as humans

    • Macaques show discrimination peaks at human VOT and place-of-articulation boundaries

  • Innate & Acquired

    • Infants born with ability to make many speech discriminations that they can subsequently NOT make

    • Adults have lost the ability to make distinctions that their language does not use

  • Each language has its own distinctive set of phonemic categories

    • English distinguishes /r/ from /l/  but Japanese doesn’t

    • Tamil distinguishes dental /t1/ from an alveolar /t2/ from a retroflex /t3/.  English doesn’t.

  • Phonemes in a particular language are defined by minimal pairs

    • i.e. since in English “lice” and “rice” have a different meaning, then they contain different phonemes: /l/ and /r/

    • But there is no such minimal pair in Japanese, so they have a single phoneme /r/

  • Can Japanese really not hear any difference?

    • For English speakers /d/-/g/ boundary is in a different position after /l/ than after /r/.

    • This is also true for Japanese who can hear /r/ vs /l/

    • But ALSO true for those who can’t.

    • Is this because of language knowledge (implicit phonetics)? No, its phoneme distinction.

    • QUAILS DO IT TOO  !!!

Auditory Agnosia

  • Definition

    • The defective recognition of auditory stimuli in the context of preserved hearing – as tested with audiometry

    • Primary signs

    • Difficulty in understanding the meaning of spoken words

    • Can refer to a generalized disorder affecting perception of all types of auditory stimuli including non-verbal sounds, speech and music

  • Associated with bilateral, or unilateral lesions of the left superior temporal cortex

    • Although some cases have been described following unilateral right temporal lobe damage

  • By far the most common cause is cerebro-vascular accident

    • But some cases have been reported following encephalitis

  • Types of sound recognition disorders

    • 1. Apperceptive

      • Impaired acoustical analysis of the perceptual structure of an auditory stimulus

      • (frequency, pitch, timbre)

    • 2. Associative

      • An inability to associate a successfully perceived auditory stimulus with a conceptual (semantic) meaning

  • Spoken Word recognition

    • Morton’s 3-stage model

      • Auditory analysis system = identifies phonemes in the speech wave

      • Auditory input lexicon = identifies the phonological properties of known words

      • Semantic system = identifies the meanings of known words

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Gestalt

Gestalts

1. Find component parts

Separate from background

Figure from ground

What part of the image becomes the figure:

bounded (closed) area

symmetric area

brighter area

smaller area

convex area

meaningful

identified

near

2. Group according to built-in rules

Deciding which parts go with what objects

10 Gestalt Principles

Figure & Ground

Similarity

Angle

Form

Brightness

Proximity

Closure

Pragnanz

Good Continuation

Symmetry & Convex

Set & Context

Common Fate

Wertheimer’sPhi Phenomenon

THE THEORY

Perception is the formation of “Gestalts”

Doesn’t translate easily to English

configuration, form, holistic, structure, and pattern

Concerned with how phenomena become organized into whole meaningful figures

Visual perception is an active creation

not merely the adding up of lines and movement

3 Gestalt assumptions

1. Perceptions are formed by automatic processes

2. Perception based on wholes

3. Perceptions are integrated wholes

Problems with Gestalt theory

Gestalts are difficult to describe objectively

Gestalt formation is difficult to predict

No idea how Gestalt formation occurs

eg, built in, learned, incremental, parallel, sequential

 

 ILLUSIONS

•      False perceptions

–   People don’t perceive length, area, angle, brightness they way they “should”

–   Systematic perceptual errors

•      Brightness contrast

Grey square on white background

•      Delboeuf Illusion

Compare outer to inner

•      Estimation

Height of 4-story building overestimated by 25%

Horizontal-Vertical Illusion

Impossible Objects

 

 THE PEOPLE

Max Wertheimer (1880-1943)

Phi Phenomenon

A Challenge to Wundt’s psychology

Perception of apparent movement

Kurt Kofka (1886-1941)

The Growth of the Mind (1921)

Perception has a broad concern

Should not be thought of as a narrow focus on a single process

Wolfgang Köhler (1886-1941)

Spokesman for Gestalt movement

insight versus trial-and-error learning

immediate apprehension

learning involves a reorganization of the psychological environment

molar (Gestalt) versus molecular (behaviorist) view

The Mentality of Apes

 Productive Thinking

Going from confusion to a new state in which everything is clear, makes sense, and fits together

Isomorphism

There is a correspondence between psychological experience and the underlying brain experience

Kurt Lewin (1890-1947)

Founder of modern social psychology

Sensitivity Training Groups

Social Action Research

Group Dynamics

Field Theory

Life space

Zeigarnik effect

the tendency to recall uncompleted tasks more easily than completed tasks

Fritz Perls (1893 – 1970)

Philosophy

Existential & Phenomenological

Grounded in the client’s “here and now”
Goal is for clients to gain awareness of what they are experiencing and doing now
Direct experiencing rather than the abstractness of talking about situations
Rather than talk about a childhood trauma the client is encouraged to become the hurt child

Theory

Self understanding comes from how behave in the present

Holistic approach to personality

Focus on “process”

Therapy

Clients are manipulative

Resist change

Avoid taking on personal responsibility

Prefer environmental support to self-support

Unaware of their psyche

Reintegrate newly disowned parts of personality